This invention relates generally to a valve, and more particularly pertains to an equilibrium valve wherein it may be set to pass pressurized fluid including gas within a particular range but curtailing the flow of such fluid when that pressure range is exceeded.
A variety of shut-off, surge or lock-up single or double acting valves for use in regulating the flow in fluid, such as a gas, are provided in the prior art. And, as can be seen from such prior art, and in particularly referring to the prior U.S. patent to Sprague, U.S. Pat. No. 2,403,689, it can be seen that the concept of providing a double acting type of device for curtailing the flow of fluid through a valve is disclosed, and which incorporates a pair of springs at opposite sides of a valve head so as to regulate its functioning for preventing the flow of fluid, particularly if a failure occurs in the downstream side of its connected flowline. As can be seen in the operation of this Sprague device, as fluid pressure enters into the inlet side of the shown device, sufficient pressure builds up so as to move its internal piston structure against the bias of one of the springs, thereby allowing a pair of valve members to separate from their sealed engagement, but that should a fracture occur in the outlet line, as previously alluded to, and cause some leakage, then the back pressure that develops results in the shiftable valve member being no longer maintained in its opened capacity, but rather, that it seats positively against the tapered valve end, thereby sealing off the further flow of fluid through the valve device. Thus, this particular lock-out device, while being generally structured and fabricated to provide a double acting form of valve closure in its features is actually designed, structured, and operated to function directly oppositely from that which has been devised for the current invention, and that is to provide a valve that is designed to provide for reclosure in the event that too much or too excessive of a pressure of fluid is exerted from the incoming line, rather than have the valve function only in the event that a failure occurs at the outlet side of the apparatus at which the valve is installed.
The cut-off valve shown in the U.S. Pat. No. 2,351,035, to Grant, Jr., discloses a similar type of valve mechanism to that as previously explained, wherein its disc valve is apparently normally maintained open, but which will automatically close by the increase in the rate of flow of the fluid medium therethrough beyond a predetermined amount as previously gauged. But, once again, this valve is primarily for use in determining when breakage occurs at the downstream side of the valve, rather than to act as a means for regulating the operations of the valve against the excessive flow of pressurized gas from a pressure vessel as when it may be exceeded beyond that previously set by the on-off regulator.
The U.S. Pat. No. 2,027,762, to Becker, discloses a valve, also incorporating a pair of biasing springs therein, but wherein both of these springs operate on the same side of the valve or closure member and its accompanying piston.
The U.S. Pat. No. 3,379,213, to Billington, discloses an excess flow check valve, and which apparently is designed for the similar purposes as the current invention, and that is to prevent a too excessive flow of pressurized fluid, as in this case, a liquified petroleum gas, through and out of a flow line. And, while this prior art invention shows the cooperation between a variety of springs for regulation of the fine adjustment of its valve member, in structure this Billington device is totally dissimilar from the fabrication of the current invention as will be subsequently analyzed herein.
The prior U.S. Pat. No. 2,245, 271, to Guill, discloses a safety cut-off valve, but once again for use in curtailing the flow of pressurized fluid in the event of a breakdown in the downstream side of the located valve. And, the structure of this Guill device is quite dissimilar from the component parts of the current invention. The construction of the current invention, as distinguished from this Guill patented device, is such that so long as its gas pressure through the valve is maintained at the adjusted and constant level, usually within some predetermined or preadjusted pressure range, that such pressurized fluid will continue to flow through the valve regardless that there may have been the development of a leak in the downstream side of the flow line, or if more gas is being consumed than had been anticipated. This would be so due to the equilibrium between that spring of the current invention's shut-off valve which normally maintains its flapper valve or valve means in closure, and that regulated pressure that is designed to just unseat the valve off of its first valve seat without urging the said flapper valve all the way towards the other gasket or second valve seat, which if such second seating occurs, then the shut-off valve will close and curtail the further flow of pressurized fluid through its housing.
The prior U.S. Pat. No. 2,729,234, to Stevenson, discloses what would appear to be a single acting surge valve wherein the fluctuation in pressure and flow or counterflow is taken out of the fluid line through its operations. On the other hand, there are some mechanisms within this Stevenson surge valve that have some relationship to the current invention, and that is the use of a piston that moves slidably within the valve body for either opening or providing closure in its operations but these mainly are determined through the orientation of these various discrete biasing structures and their settings within the valve body.
Finally, the prior U.S. Pat. No. 3,910,306, to Ohrn, the U.S. Pat. No. 4,049,016, to Henry, the U.S. Pat. No. 3,138,174, to Gilpin, and the prior U.S. Pat. No. 3,439,704, to Berglund, disclose other forms of more intricate types of cut-off or shut-off valves for use in regulating gas flow. More specifically, the piston like double acting valve assembly of the said Berglund disclosure also incorporates the double spring principle, and a variety of sliding pistons therein, but they are for use in conjunction with brake lines for providing a safety mechanism in the event that a disabling leak occurs in the brake assembly.
In view of the foregoing, it is the principal object of this invention to provide a shut-off valve that can be adjusted to open, function and to maintain a position of equilibrium wherein pressurized fluid may pass through the valve within a particularly set pressure range, but that when that pressure is exceeded, the valve will shut-off and curtail further flow of fluid therethrough.
A further object of this invention is to provide a double acting form of valve wherein a flapper valve is adjusted between a pair of spring means which are sensitive to both the physical setting of the valve, and the degree of pressure being exerted upon the valve by fluid passing therethrough.
Another object of this invention is to provide a safety valve that can be conveniently inserted into the outlet flow line from a regulator or its associated container of bottled gas.
Another object of this invention is to provide a shut-off valve wherein its particularly configured structure includes a series of interrelated passageways that unobstructably allow the flow of gas through the valve during normal operations, but that when the adjusted parameters for operation of the valve are exceeded, the valve will immediately shut-off.
Yet another object of this invention is to provide an adjustable shut-off valve that can be conveniently set simply through the use of a tool to operate within particular pressure ranges for a fluid or gas to be conveyed through the same.
Another object of this invention is to provide a safety shut-off valve that can be conveniently installed with little effort and expeditiously.
These and other objects will become more apparent to those skilled in the art upon reviewing the summary of this invention, and upon undertaking a study of the description of its preferred embodiment in view of the drawings.